1. A Framework for Regional Agroecosystems Characterization Using the National
Resources Inventory
M. R. Burkart *, S. L. Oberle, M. J. Hewitt and J. Pickus
Abstract
An agroecological framework is used to examine the relations among natural resources
and agriculture. Spatial representation of selected agroecosystems characteristics was
accomplished using the National Resources Inventory (NRI). Natural resource and
anthropogenic variables from the NRI were spatially aggregated to produce maps
showing the regional variability in area-weighted values of agroecosystem
components. Maps of natural vegetation, agricultural land use, crop diversity, artificial
drainage, irrigation, net soil loss, and conservation practices show the extent to which
resources have been modified to support agriculture in the Midwest. The frequency of
land used for crops and pasture exceeds 70% in much of the region. Natural
vegetation occupies less than 10% of the land in many areas. Subsurface and surface
drainage, more than 35% of some areas, has contributed to loss of wetlands having a
direct effect on water quality. Irrigation has diverted water from natural ecosystems and
increased the potential for leaching of agrichemicals. Excess erosion may threaten
long-term productivity in parts of the region even though conservation practices have
been implemented. Examination of these and other elements in an agroecosystem
framework may be useful in the search for systems to sustain agriculture and natural
resources in the region. Such a framework can also be used to locate areas where
mitigation of degraded resources is most needed; identify areas where research into
causes of degradation can yield the most information; and where policies to improve
off-site damage may be most effectively implemented.
Journal of Environmental Quality: Vol. 23 No. 5, p. 866-874